AC-PC Line

The AC-PC line is an auxiliary line that runs through the anterior commissure (AC) and posterior commissure (PC).

Clinical application

The AC-PC line is particularly used in neuroradiology and is often employed as a reference for axial slicing in MRI. The AC-PC line is also used in functional neurosurgery, which has historical backgrounds, as early neuroanatomical atlases used the AC-PC line for slicing.

Definition according to Talairach

According to the definition by Talairach[^1], the AC-PC line runs through the superior boundary of the anterior commissure and the inferior boundary of the posterior commissure.

Definition according to Schaltenbrand

According to the definition by Schaltenbrand[^2], the AC-PC line runs through the midpoint of the anterior and posterior commissure, allowing both commissures to be displayed on a thin axial MRI slice.

Difference

The Talairach and Schaltenbrand definitions differ by 5.81° ± 1.07°[^3].

Imaging